As the computation performance of the currently available mobile devices, personal computers, severs, communication cabinets and other systems or devices has been largely upgraded, heat generated by computation units in these systems or devices is also largely increased. Therefore, heat dissipation units are required to dissipate the heat. Different heat dissipation units, such as heat sinks, heat pipes and vapor chambers, are widely used with cooling fans to enhance heat dissipation. Among others, vapor chambers are normally used with fans to enable forced heat dissipation from a large area. To avoid thermal resistance effect, the heat dissipation elements must be tightly attached to one another. Generally, the vapor chamber is a flat plate internally defining a chamber for vapor/liquid circulation to transfer the heat. Furthermore, the vapor chamber is internally provided with a plurality of supporting posts to support the chamber, lest the vapor chamber should expand or deform under heat or pressure.
The vapor chamber spreads the heat from one area to another area, and is provided with a plurality of supporting posts therein to avoid expansion or deformation under heat or pressure. However, it requires additional labor and time and increased manufacturing cost to provide the supporting posts. In the case copper cylinders externally combined with sintered rings are used as the supporting posts of the vapor chamber, the copper cylinders serve to support the chamber and the sintered rings enable back flow and circulation of the working fluid. In this case, the vapor chamber tends to have uncontrollable bottom flatness. Or, in the case copper cylinders with multiple grooves are used as the supporting posts of the vapor chamber, the copper cylinders serve to support the chamber and also enable back flow and circulation of the working fluid. In this case, the vapor chamber also tends to have uncontrollable bottom flatness. The vapor chamber can be otherwise internally etched to directly form supporting posts and vapor passages or flow channels on its inner wall surfaces. However, it requires more time to do so. Further, deeper etching requires longer time. Other processes, such as washing, drying and so on, also extend the manufacturing time.
In view that the conventional technique for solving the problem of a deformed vapor chamber also brings the problems of increased manufacturing costs and uncontrollable bottom flatness of the vapor chamber, it is desirable to work out a way to reduce the manufacturing cost.